Wednesday, January 27, 2010

purports to manipulate the body's energy field by tapping on acupuncture points while a specific traumatic memory is focused on, in order to alleviate a psychological problem. Critics have described the theory behind EFT as pseudoscientific and have suggested that any utility stems from its more traditional cognitive components, such as the placebo effect, distraction from negative thoughts, rather than from manipulation of meridians.

EFT, a form of Thought Field Therapy (TFT), has been thoroughly debunked as pseudoscience by the Skeptical Inquirer:

. . .EFT is very similar to TFT, except that it employs one simplified and ubiquitous tapping procedure instead of applying different algorithms to treat different problems. On his Web site, [Gary] Craig1 asserts that Callahan’s reliance on differing algorithms is unnecessary because he has witnessed TFT therapists tap in the wrong order or apply the wrong algorithm to the particular problem and still obtain improvements. Craig’s anecdotal evidence appears to contradict Callahan’s anecdotal evidence. Furthermore, Craig extends his tapping therapy far beyond the realm of mental health, reporting testimonials from individuals who claim to have successfully used EFT to treat everything from autism to warts and various other medical problems with positive results...

A scientifically minded investigator would have then taken Craig’s observations a step further and tested a completely "placebo” algorithm which did not tap on any supposed energy meridians to see if it produced similar results. However, Craig reports that he has never carried out this simple experiment nor does he know of anyone who has. Furthermore, Craig speculates that a placebo algorithm may be impossible because tapping anywhere on the body will affect the body’s energy meridians. This position conveniently renders Craig’s theory unfalsifiable and therefore outside the realm of science.

EFT therapists can act as surrogates, tapping on themselves to cure the problems of others. But even more fun than that, why use yourself as a surrogate when you can tap on a cute magical teddy bear? Really and truly? According to Craig:

It is easily explainable in spiritual terms (we are all connected) and through the findings of quantum physics.

But it would behoove him to read a physics textbook, as well as the Skeptic's Dictionary: "This is the golden rule for New Age quacks: when in doubt, quote Einstein and mention quantum physics... What Gary forgets to tell us is that the so-called subtle energy of acupuncture has nothing in common with the energy in E=mc2. When you unblock that kind of energy you get nuclear weapons or power, not miraculous health cures."

EFT therapists have also resorted to those trendy media favorites -- mirror neurons! -- to explain their quackery:

It's been shown in scientific experiments that when one animal is doing something such as eating a banana, another animal who is merely watching will have the same neurons lighting up in their brains as the animal who is doing the activity.

Likewise, in tests done with acupuncture, when needles are being inserted into points on one person, the same points are lighting up on a person who is only observing. In the case of the Magical Bears, we might conclude that when you are tapping on the bear, as you tap, your points would be lighting up as well.

hat tip: AA

Everyone knows what mirror neurons are, those darlings of the pop neuroscience world. First observed in the ventral premotor area F5 of macaque monkeys, mirror neurons increase their rate of firing when the animal performs an action, and when the animal watches someone else perform the action (Rizzolati et al, 1996). These "monkey see, monkey do" neurons have taken on a life far beyond their originally postulated role in imitation. However, not everyone believes that mirror neurons can account for all aspects of human language, culture, and social cognition -- from empathy to altruism to autism to aesthetics to

The idea that these particular cells might underlie a fundamental human impulse [altruism] reflects the emergence of a new scientific myth. Like a traditional myth, it captures intuitions about the human condition through vivid metaphors.

As long-time readers might know, mirror neurons have been a popular topic of ridicule throughout the entire four year history of this blog. For your celebratory reading pleasure, here's The Neurocritic's mirror neuron œuvre:

1 "Gary Craig is not a licensed health professional and offers EFT as an ordained minister and as a personal performance coach. Please consult qualified health practitioners regarding your use of EFT."

Twitticism: "Mirror neurons can explain everything. We can all go home now."

Tuesday, January 19, 2010

Fig. 2 (Schaefer & Rotte, 2010). Example of a questionnaire used to form a semantic differential for one particular brand. Subjects had to rate the brands according to their relationships to 18 pairs of contrary adjectives.

The nascent field of neuromarketing has grown tremendously in the last 5 years. Its goal is to use brain imaging techniques such as fMRI and EEG to gain hidden insights into consumer preferences. Commercial applications have far outstripped the peer-reviewed science necessary to validate their use. Google returns 322,000 hits for the term neuromarketing, whereas PubMed coughs up a sorry number - only 5 references! That doesn't stop large corporations from funneling millions of dollars into neuromarketing.

A new study published by Schaefer & Rotte, 2010 combined the techniques of semantic differentials (rating products along a 7 point scale between 2 bipolar adjectives, as shown in Fig. 2) with fMRI. First, participants viewed 18 pictures of common pharaceutical brands, such as aspirin. They were asked to rate these stimuli on a 5-point-scale regarding their personal attractiveness. After the imaging session was over, they completed the semantic differential questionnaire. These ratings were used to analyze the fMRI data.

Is this aspirin playful or serious?

Fig. 3 (Schaefer & Rotte, 2010). Semantic space built by the results of the semantic differentials. Brands and concepts are displayed on a 2D schema (factors ‘social competence’ and ‘potency’; factors were orthogonal). Colored circles depict the different brands. [NOTE: click on the figure for a larger view, and you can see the adjectives used in the present study are depicted in light blue.]

I knew next to nothing about semantic differentials before reading this paper, and that state of ignorance did not improve much when I finished reading. Some of the concepts were really murky and dependent on familiarity with the literature from 1957 and/or in German:

...Although semantic differentials have been investigated for decades, the correct description of these factors remains an issue. Thus, different researchers have been using very different labels for the underlying factors. This is particularly true for the factor ‘evaluation’ (Osgood et al., 1957), which also has been described as ‘mother’ [in a psychoanalytic view (Hofstätter, 1957)] and more recently as ‘social competence’ (Dziobek and Hülser, 2007).

The terms "evaluation", "mother", and "social competence" do not seem remotely equivalent. A book chapter by David Heise (1970) provided some clarity on the methodology:

(2) Ratings on bipolar adjective scales tend to be correlated, and three basic dimensions of response account for most of the co-variation in ratings. The three dimensions, which have been labeled Evaluation, Potency, and Activity (EPA), have been verified and replicated in an impressive variety of studies.

(3) Some adjective scales are almost pure measures of the EPA dimensions; for example, good-bad for Evaluation, powerful-powerless for Potency, and fast-slow for Activity. Using a few pure scales of this sort, one can obtain, with considerable economy, reliable measures of a person's overall response to something. Typically, a concept is rated on several pure scales associated with a single dimension, and the results are averaged to provide a single factor score for each dimension. Measurements of a concept on the EPA dimensions are referred to as the concept's profile.

So why is a brand of aspirin rated on the dimension of seclusive--sociable? Because the results here were incorporated into a larger semantic space established in an earlier study. Principal component analysis reduced the dimensionality of the data to two main factors that accounted for 87% of the variance: ‘evaluation’ and ‘potency’. The authors didn't like ‘evaluation’ for some unexplained reason and instead used the term ‘social competence’ for a series of inanimate pharmaceuticals. [NOTE: Guess I'm not a marketer...]

Moving on to the fMRI aspect of the experiment, it seems the authors wanted to relate the social competence of drug brands to neural activity in the medial prefrontal cortex (MPFC), which has been associated with self-referential processing and social cognition.

Fig. 4A(Schaefer & Rotte, 2010).Contrasts of brands loading high on the factor ‘social competence’ compared with brands loading high on the factor ‘potency’. This contrast showed significant activation in the MPFC and the SFG (superior frontal gyrus).

Oddly, the reverse contrast of high potency brands vs. high social competence brands did not produce any significant activity in the brain at all, which seems unexpected for a series of drugs. The high potency vs. low potency comparison revealed a reduction in SFG activity. To explain these results, the authors comitted the logical fallacy known as "reverse inference" by inferring the participants' mental state from the observed pattern of brain activity.

fMRI enable us to link the factors driven out of the behavioral data with the activation of certain cortical areas. Since the functional meaning of those areas (the MPFC and the SFG) are known from previous studies, the results can tell us what the extracted factors are about. More in detail, the results suggest to mark the factor originally described as ‘evaluation’ now as being mainly characterized by social perceptions. Thus, the description ‘social competence’ for this factor seems to be much more appropriate. Hence, the fMRI results provide important improvements for the factorial model of semantic space, which would not have been possible by looking on the behavioral data alone.

As for the SFG, they'd like to relate greater activity there to enhanced cognitive effort and working memory, but acknowledged this caveat:

However, since the SFG has been related not only to working memory but also to a variety of different cognitive functions, these explanations remain speculative.

Overall, I'm not sure how Bayer can target a new marketing campaign based on these results. The social competence of doctors recommending the aspirin, as in the classic commercial below? Comments, anyone?

Thursday, January 14, 2010

A sense of agency is the feeling that you're initiating and controlling your own movements. This can go awry in schizophrenia, when individuals can experience delusions of control (Lafargue & Franck, 2009). In this state, the patient feels as if external forces are performing actions against his will. Loss of agency also occurs in alien hand syndrome, a rare and unusual neurological disorder in which the affected patient loses volitional control of one hand, which develops "a mind of its own."

A recent fMRI study looked at the pattern of neural activation associated with a sense of agency in normal participants (Yomogida et al., 2009). To do this, they used a "violation-of-visual-feedback paradigm" as shown below in Fig. 1. Subjects played a video game in which they controlled the movement of a character using a joystick. In the control condition, audio feedback was provided when they hit one of the targets (tomato - "squish" or balloon - "pop"). In the agency violation condition, the computer program moved the character in a different direction than the subject intended. In the sensory-matching violation condition, either the wrong feedback sound was presented, or the correct feedback was presented at the wrong time. A separate "oddball" task did not involve a motor response but controlled for the infrequent occurrence of the violation conditions.

Fig. 1 (Yomogida et al., 2009). Task paradigm of the agency and SM error task. On each trial, a target (red object) was presented in one of four locations on a screen. Subjects were asked to hit the target by controlling the character using a joystick. Three conditions were possible: control (C), agency violation (AGv), and sensory-matching violation (SMv).

A region of particular interest for alien hand syndrome is the SMA, which is involved in the planning, initiation, and inhibition of motor responses. An older paper by Feinberg et al. (1992) identified two alien hand syndromes. One of these is associated with damage to the anterior corpus callosum, as happens in the classic "split brain" operation to sever the white matter connections between the two cerebral hemispheres (undertaken for seizure control). The more "alien" (or anarchic) of the syndromes involves damage to dorsomedial frontal cortex, including the SMA and the anterior cingulate.

However, note in Fig. 3 above that the "activation" in SMA is actually manifest as a smaller reduction in activity for agency errors compared to sensory matching errors. What does this mean? The authors don't say.

Activation of the cerebellum was linked to cerebellar abnormalities in schizophrenic patients who experience delusions of control. In contrast, the authors discounted the importance of occipito-temporal and posterior parietal regions for a sense of agency, since there was some increased activity in these areas for oddball errors, as well as agency errors. But in a recent brain stimulation study, Desmurget and colleagues (2009) implicated posterior parietal cortex in the intention to move:

Stimulating the right inferior parietal regions triggered a strong intention and desire to move the contralateral hand, arm, or foot, whereas stimulating the left inferior parietal region provoked the intention to move the lips and to talk. When stimulation intensity was increased in parietal areas, participants believed they had really performed these movements, although no electromyographic activity was detected. Stimulation of the premotor region [which did not include SMA] triggered overt mouth and contralateral limb movements. Yet, patients firmly denied that they had moved. Conscious intention and motor awareness thus arise from increased parietal activity before movement execution.

Here's a documentary about alien hand syndrome and the brain, circa 1993 (or maybe 1996). You'll have to sit through the melodramatic narration, the overwrought music, and the cheesy reenactments to watch interviews with afflicted patients and with Todd E. Feinberg, Joe Bogen, and Eran Zaidel.

You can read more about alien hand and willed actions in these blog posts:

One of these, the Fujiyama, is the world’s highest roller coaster at 259 feet. It has a drop of 230 feet at an angle of 65° and has the world’s fastest speed of 81 mph. There was no direct trauma to her head or loss of consciousness during the rides.

The headache started when she was on her way home from the park. She went to the hospital when it persisted for 4 days.

The woman’s headache was constant, mainly suboccipital, worse in the evening, and partially relieved by rest. ... Neurologic examination results were normal. Her pupils were equal and reactive to light, and there was no papilledema or retinal hemorrhages. Routine laboratory tests for blood and urine all were normal. Tension-type headache was initially diagnosed, and muscle relaxants were prescribed for 4 weeks with some benefit; the headaches fluctuated but were unrelieved.

Two months later, MRI of the head ruled out an organic problem and showed bilateral subdural hematomas with neomembranes.

Another paper compared head motions that occurred in 4 participants when they rode 3 different roller coasters at Six Flags, drove bumper cars, and had a pillow fight (Pfister et al., 2009). What are the implications for brain injury? they asked.

The 18 mph (8.1 m/s) car crash simulation resulted in the highest measurements of linear acceleration, linear velocity, and rotational velocity of the head. The highest level of rotational acceleration was measured during the pillow fight. Interestingly, the pillow fight generated peak head accelerations and velocities greater than the 3 roller coaster rides. Despite the difference in the 3 roller coaster rides (ie, speed, turns, loops), they lead to similar head motions. It is important to note that variations in head motions were small between the roller coaster rides, pillow fight and 5 mph (2.2 m/s) car bumper hit.

Mostly dismissive of the case study literature on roller coaster headaches, these authors ended on a pro-roller coaster note:

Our current empirical data supports 2 scientific panels' opinions as well as previous results from a computational model. Specifically, head motions during roller coaster riding fall within the range of normal activities and are far below thresholds of TBI in normal individuals.

An increasing number of U.S. adults are being prescribed combinations of antidepressants and antipsychotic medications...

. . .

To examine patterns and trends in psychotropic polypharmacy—or the prescription of more than one psychiatric medication—[Mojtabai & Olfson, 2010] analyzed data collected from a national sample of office-based psychiatry practices. The number of medications prescribed and specific medication combinations were assessed from a total of 13,079 office visits to psychiatrists by adults (18 years or older) between 1996 and 2006.

. . .

"The increasing trend of psychotropic polypharmacy was mostly similar across visits by different patient groups and persisted after controlling for background characteristics," the authors write. Combinations of antidepressants with sedative-hypnotics were the most common medication combinations overall (23.1 percent), followed by combination of antidepressants with antipsychotics (12.9 percent) and combinations of two types of antidepressants (12.6 percent).

"While the evidence for added benefit of antipsychotic polypharmacy is limited, there is growing evidence regarding the increased adverse effects associated with such combinations," the authors write.

The majority of treated patients, nearly 45 percent, received psychotherapy with no medication. Only 34 percent of patients were prescribed antidepressants. Of that number, Mexican Americans and African Americans were prescribed antidepressants a third less often than Caucasians. Factors such as education, health insurance and income did not explain the lower rates of medication use.

Many U.S. adults with major depression do not receive treatment for depression or therapy based on treatment guidelines, and some racial and ethnic groups have even lower rates of adequate depression care...

. . .

[González et al., 2010] assessed the prevalence and adequacy of depression care among different racial and ethnic groups in the United States by analyzing data from the National Institute of Mental Health's Collaborative Psychiatric Epidemiology Surveys. This initiative combines three nationally representative studies, during which face-to-face interviews were conducted with 15,762 individuals age 18 and older throughout the country between 2001 and 2003.

Of the adults surveyed, 8.3 percent had major depression, including 8 percent of Mexican Americans, 11.8 percent of Puerto Ricans, 7.9 percent of Caribbean blacks, 6.7 percent of African Americans and 8.5 percent of non-Latino whites.

Overall, more than half of those with depression received at least one form of depression care, but only about one in five (21.3 percent) had received at least one form of therapy that conformed to established treatment guidelines within the previous year.

About Me

Born in West Virginia in 1980, The Neurocritic embarked upon a roadtrip across America at the age of thirteen with his mother. She abandoned him when they reached San Francisco and The Neurocritic descended into a spiral of drug abuse and prostitution. At fifteen, The Neurocritic's psychiatrist encouraged him to start writing as a form of therapy.